Nortel Circuit Card Installation Manual page 632

Page 632 of 906
Figure 143
E&M trunk card – block diagram
Input/output
Front
panel
LED
Card slot
address
Back-
plane
Async card
LAN link
Tx PCM
Rx PCM
Con-
troller
card
5.12 MHz
clock
1 kHz
frame sync
+8.5 V dc
Power
supplies
553-3001-211 Standard 3.00
NT8D15 E&M Trunk card
interface
control
Address/
data bus
PCM
Micro-
controller
Card LAN
interface
DS-30X
interface
Signaling
and status
Control
logic
Reg + 5 V dc logic power
• Software control of A/µ-Law mode.
• Software control of digit collection.
August 2005
Trunk interface units 0–3
Codec
Line interface unit power
Trunk
signaling
interface
+ 5 V dc
analog
hybrid
±15 V dc
analog
power
Tip/ring
Analog
(2/4 wire)
XFMR
hybrid
Voice
band
Signaling relays
(ringing, battery
reversal)
E&M
Sup.
Loop current/
signaling
dialpulse detect
Ringing
Ð 48 V dc Rsync
battery
Facility
services
interfaces
(2-W E&M,
4-W E&M,
and Paging)
Signaling
interface
553-6201